Bernard Tomic, the Australian tennis player whose father and coach John has been barred from ATP tournaments. Photograph: Rick Rycroft/AP

Bernard Tomic's father and coach John Tomic has been barred from all ATP tournaments until further notice as he faces charges of assaulting his son's practice partner.

John Tomic on Monday appeared in a Madrid court, where he denied charges of assaulting Thomas Drouet shortly after their arrival in the city for the Masters Series event.

In a statement on Tuesday, the ATP said: "Following last week's incident in Madrid concerning John Tomic, and the ensuing investigation, Mr Tomic's credential privileges have been suspended at all ATP tournaments until further notice. The ATP's investigation into this incident remains ongoing." A second court hearing has been scheduled for 14 May.

Drouet expressed his sympathy for the Australian No1 after claiming he had been headbutted by the player's father.

The Frenchman, who left the court with bandages over his nose and left eye, told Fox Sports: "I feel bad for Bernard because he is a person who must feel sad for what his father is doing. I wish him all the best. Bernard is a nice guy. I will recover and see what happens."

Drouet alleges the incident was sparked by a row at Nice airport prior to leaving for Madrid. He then claimed that when they arrived in the Spanish capital, Tomic senior asked to walk with him before the altercation took place.

Drouet added to www.news.com.au: "Outside the Cuzco hotel he comes up to me and I think he is about to apologise [for the incident in Nice] and he says come over here with me.

"So I walk with him maybe 100 metres and he is doing this [looking about], like looking about for a place. It was away from the front. He then says the same things and then spits in my face.

"I took steps back and say: 'OK John, you are a real man.' And then I say: 'OK don't pay me, Bernard will pay me'.

"He suddenly turns and headbutts me right here [points at bridge of nose). I call out 'help' and then I fall down. I am out 10 to 15 minutes, I didn't know – that is what I am told.

"I lost consciousness, I blanked out. I was told after this headbutt he just walked back to the hotel like normal, like nothing happened."

Tomic's lawyer Carmen Dieguez painted a different picture and insisted Drouet was the aggressor. "[Tomic] claims [Drouet] was the aggressor and grabbed him," Dieguez told the same website.

"He feels it was self-defence and he does not believe he was responsible for what happened."

Speaking as he left the court, John Tomic said: "I don't feel guilty. I didn't do anything wrong."

After a bright start to the season which saw him win his maiden ATP title in Sydney, the 20-year-old Bernard's form has tailed off and he lost his opening match in Madrid on Monday to the Czech Radek Stepanek.